looking at how much talent they had in 2015.

Just because someone was drafted in 2020 but was on the 2015 team does not mean they were good enough to be drafted in 2015. As I said, talent comes over time, experience, etc.

Zach Wilson was drafted after 2020, but if you pointed at BYU's 2018 or 2019 team, you would not have said, "see Zach Wilson's talent is worthy of an NFL spot."

We are not comparing the "potential" of a team. We talking about the current "talent" level of team. A 2015 freshman in college who didn't contribute until later, is not "NFL talent" in 2015. In 2015, that team had 12 NFL talent caliber players, maybe a few more that didn't go into the draft, but they did not have 41 more players that were NFL caliber.

Even the vaunted 2015 Ohio State team cannot compete talent wise with an NFL team. There are so many colleges and only the best of the best move on to the next level because there are so few NFL teams by comparison. Depth and caliber at every position is too much better.